Variable condenser



April 194-8- I c. v. LITTON 2,438,931

VARIABLE CONDENSER Filed March 15, 1944 IN VEN TOR. 09454419 k 1 /nzw ATTE/VEY Patented Apr. 6, 1948 VARIABLE CONDENSER Charles v. Litton, Redwood City, Calil., assiznor to Federal Telephone and Radio Corporation,

New York, N. Y.,

a corportion o! Delaware Application March 15, 1944, Serial No. 526526 I 6 claim. (CI. 175-415) u 1' This invention relates :to 'variable condenser-s and particularly to such condensers arranged to be operated in an atmosphere of reduced pres- A sure.

One of the objects of the invention is to provide a vacuum condenser, the capacity of which may be varied by rotating the envelope thereof.

Another object of the invention is to provide a vacuum variable condenser which is easy to construct and which may be easily and accurately adjusted.

Other objects of the invention will be apparent as the description thereof proceeds.

One embodiment of the invention is il1us-' trated in the accompanying drawing in which the single figure is a sectional side elevationa view of the condenser, showing the manner of mounting the rotating parts.

The condenser of the invention is enclosed in an envelope I which may be of glass or other 'suitable insulating material and which may be globular in form. The envelope I is provided with .openings at opposite ends; concentric with a hoti-- zontal axis about which the envelope is adapted to be rotated for tuning the condenser. The rim of the opening on one end is fused, as at 2, upon the fiared edge 3 of a metal sleeve 4. The other opening in the envelope l has its rim fused, as at 5, to the fiared edge 6 of a metal sleeve '1. The sleeves 4 and 'I are in alignment with the rotating axis and are rotatably mounted in bearings 8 and 9, respectively, these bearings being supported on suitable pedestals o and ll which,

in turn; may be supported upon an insulating base l2. The outside electrical connections to the condenser are made through the bearings 8 and 9 by the wires |3 and 14, respectively, which ;are connected to the bearings by suitable means, such as the screws |5, shown attaching the pedestals ID and Il to the base I2.

Inside of the sleeve 4 I provide another sleeve I'l which has azclose fit with the sleeve4 and is welded to it or is in such close contact therewith as to provide a good electrical connection between the two sleeves and prevent relativ movement therebetween. Similarly a sleeve !8 is provided within the sleeve 1. The sleeves i' and s are cut diagonaily within the envelope l so as to form xtended portions !9 and 20 the ends of which are spaced a short distance from each other ad- I jacent the center of the envelope I.

A 'plurality of rotor plates 2l are attached to the portion IS of the sleeve l'l and extend outwardly therei'rom perpend icular to the rotating 2 axis. Similarly, a plurality of rotor piates 22 are attached to the portion 20 of the sleeve s and extend outwardly therei'rom perpendicular to the axis of the condenser. The two sets of rotor plates !I and 22 are aligned, and all rotate when the envelope i is rotated. The rotor plates z are elect'ricaly connected to the wire l3 through the sleeves I'I and 4 and the hearing 3. Similarly the rotor plates 22 are eiectrically connected to the wire |4 through the sleeves |8 and 1 and the bearing 8.

The outer end of the sleeve I'I is turned inwardly to form a smaller diameter sleeve 23 to the end of which is fused a short tube 24 of insulating material, such as glass. The other end of the tube 24 is fused to the outer end of a short metal tube 25 which forms a hearing for a cylinder 26 which is preferably made of a, material having a low friction characteristic, such as graphite. A groove 21 may be provided in the tube 25 to limit movement of the cylinder 26 towards the sleeve 24, and the inner end of the sleeve 25 may be spun over, as at 28, to limit the movement of the cylinder 26 in the other direction.

The outer end of the sleeve l8 is likewise turned inwardly upon itself to form a sleeve 29 to the end of which is fused an insulating sleeve 30 :f glass or other suitable material. A metal sleeve 3i is !used to the inner end of the sleeve 30 and forms a hearing for a cyiinder 32 which is similar to the cylinder 26. The sleeve 3l may be provided with a groove 33 to prevent outward i movement of the sleeve 32 and the inner end may be spun over, as at 34, to prevent movement of the sleeve 32 in the other-direction.

A sha!t.35 is mounted between the two cylinders 26 and 32'and concentrically therewith, the cylinders being preferably molded to the ends of the shalt. The shaft is preferably made of steel or other material having low electrical conductivity. Thus constructed, the shaft 35 is rotatably mounted within the sleeves l'i and |8 and insulated therefrom by the insulating sleeves 24 and 30. The cylinders 26 and 32, being preferably made of graphite, will have very little friction with the sleeves 25 and 3I, so that the shaft 35 may rotate very freely.

At the center of the shalt 35 I provide an arm 36 which may be rigidly attached to the shaft in any desired manner and which carries on its outer end a weighted member 31. The outer surface or the member 31 is shaped to conorm to the inner surface of the envelope I and is spaced from that envelope. so that the shaf-t 35 can be continuousiy rotated. Upon the Inner surface of i the member 31 are mounted a. plurality ot conrotor plates 21, attached to the sleeve l1, and the v plates 39 cooperating capacitively with the rotor plates 22. attached to the sleeve l8. The

member 31 is long enough axially so that the groups of plates 38 and 39 may be properly spaced to cooperate with the rotor plates ZI and 22. The member 31 also has sufflcient weight so that it will tend to remain at its lowermost point, as indicated in the figure, regardless of how the envelope l is rotated in its bearings.

The arrangement forms in eect a dual-section condenser with two separate condensers in series, the one consisting of the rotor plates Zi and' the stator plates 38 and the other consisting of the stator plates 39 and the rotor plates 22. It will be seen that if the envelope I is now rotated, the plates 21 and 22 will turn out of cooperative relation with the plates 38 and 39 and will move into the upper portion of the envelope i, and, as they move, the Capacity of the condenser will be decreased, until the minimum capacity is obtained when the plates are at their uppermost position. In the position shown in the figure, the condenser has its maximum capacity.

Any suitable arrangement for rotating the envelope l in its bearings may be provided, as, for instance, the shaft 40 which is shown rotatably mounted in an extended portion 4! of the bearing 9 and is provided with a spur gear %2 which meshes with a gear 43 attached to the sleeve i. Rotation of the shaft 40 by means of a suitable handwheel M, for instance, will cause the entire envelope i to rotate in its bearings 8 and Q through the gears 42 and 43.

The envelope i may be exhausted of air or.

the air may be greatly reduced in pressure v through any suitable opening provided for that purpose, 'as will be understood, or the envelope may be filled with an inert gas, if so desire-d.

By the arrangement shown the stator plates 38 and 39 may be very accurately positioned with respect to the plates ZI and 22, and by means of the graphite cylinders 26 and 32, are arranged to turn very easily with respect to the rotor plates. Hence any rotational movement oi the envelope l will change the capacity of the condenser without causing the stator plates to move with respect to the base !2, the weighted member 31 holding them in substantially fixed position at the lowe'most portion of the envelope. Various modifications of the invcntion will suggest themselves to those skilled in the art, and I do not desire therefore to limit myself to the structure shown and described except by the limitations included in the appended claims.

What is claimed is: A 1. A variable condenser comprising a first fixed bearing, a second fixed bearingin alignment with said first hearing, a first metallic sleeve rotatably mounted in said first fixed bearing, said sleevebeing closed at the end away from said second hearing, a second metallic sleeve rotatably mounted in said second hearing,

sleeves, and a weighted member attached to said I stator plates and adapted to maintain said stator plates in substantially fixed position by gravity when said sleeves are rotated.

2. A variable condenser as dened in claim 1, in which the envelope and first and second sleeves form a gas tight unit from which the air has been partly exhausted.

3. A variable condenser comprising an envelope of insulating material, symmetrical about a horizontal axis, said envelope having a pair of opposed openings concentric'with said axis, a. metallic sleeve in each of said openings forming a gas tight connection with said envelope, said sleeves being closed at their outer ends so that said envelope is gas tight, two groups of thereof about said axis, and' an atmosphere of c reduced pressure within said envelope.

e. A variable condenser comprising an envelope of insulating material, symmetrical about a horizontal axis, said envelope having a pair of opposw openings concentric with said axis. a metatlic sleeve in each of said openings forming agas tight connection with said envelope, said sleeves being closed at their outer ends so that said envelope is gas 'tight, a metaliic supporting member within each of said sleeves, a group of rotor plates supported within said envelope on each of said supporting members, said rotor plates being mounted perpendicularly to said axis, a hearing member insulatediy supported upon each of said supporting members within said sleeves, a cylinder of graphite rotatably supported within each of said hearing members, a shaft supported by said graphite cy linders and concentric tlerewith, a group of stator plates mounted perpendicularly to said axis and arranged to cooperate with each group of rotor platw, means for eiectricaliy connecting said stator' plates together and for mounting said stator plates upon said shaft, 'weighted means for causing said stator plates to remain by gravity in substantially fixed position regardiess of the rotation of said envelope, and an atmosphere of reduced pressure within said envelope.

5. A variable condenser comprising an envelope of insuiating material, symmetricai about said second sleeve being closed at the end away from said first hearing, an envelope of insuiating material mounted between said sleeves and forming with said sleeves a unitary structure which is rotatable in said bearings, a first group of rotor plates attached to said first sleeve within said envelope, a second group of rotor plates attached' to said second sleeve within said envelope, a group of stator plates adapted for a horizontal axis, said envelope having a pair of opposed openings concentric with said axis, a first metalilc sleeve in 'each of said openings forming agas tight' connection with said envelope, said sleeves being closed at their outer ends so that said envelope is gas tight, a second sleeve rigidly attached within each of said first sleeves, said second sleeve having a portion extending in towards the center of said envelope and the outer end of said sleeve being turned inwardly, a tube of insulating material mounted upon each turned-in portion of said second sleeves substantially concentric with said axis, a

hearing member mounted upon the inner end of each of said tubes, a graphite cylinder rotatabiy mounted in each of said hearing members, a shaft connecting said graphite cylinders and supported thereby, a group of rotor plates attached. to the inwardiy extending portion of each of said second sieeves, a group of stator plates mounted to cooperate with each of said groups of rotor piates, means to support said stator plates from said shaft and electricaliy connect them together, weighted means to maintain said stator plates in substantialiy fixed position regardless of the rotation of said rotor plates, an atmosphere of reduced pressure within said envelope means for rotatably supporting said first sleeves, and means to rotate said first sieeves in said supporting means.

6. A variable condenser comprisng a first fixed hearing, a second fixed hearing in align-' ment with said first hearing, a. first m'etallic sleeve rotatably mounted in said first fixed bearing, a, second metallic sleeve rotatabiy mounted in said second hearing, an envelope of insulating material mounted between said sieeves and forming with said sleeves a unitary structure which go Number is rotatabie in said bearings, a first group oi rotor plates attached to said first sleeve within said enve lope, a second group of rotor plates attached to said second sleeve within said envelope, a group of stator plates adapted for capacitive cooperation with said groups of rotor plates, means to mount said stator plates rotatably within said first and second metallic sleeves, and a weighted member attached to said stator plates and adapted to maintain said stator piates in substantially fixed position. by gravity when said sleeves are rotated.

CHARLES V. LITTON.

REFERENCES The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Dete Johnson Mar. 16, 1926 Lissen July 13, 1926 Aurynger Nov. 23, 1926 Klosner Apr. 24, 1923 Murray Sept. 6, 1927 

